The present invention relates generally to manufacture of IC (integrated circuit) packages, and more particularly, to a chest of counting grids for efficiently indicating a count of IC packages within a partially filled IC package tray for a plurality of types of IC package trays.
During manufacture of IC (integrated circuit) packages, the IC packages are carried by IC package trays having a plurality of pockets with each pocket carrying a respective IC package. Depending on the size of IC packages being manufactured, different types of IC package trays have different numbers of pockets for carrying different numbers of IC packages.
Referring to FIG. 1 for example, a first IC package tray 102 has twelve pockets for carrying twelve IC packages. The twelve pockets are arranged in four rows including a first row 111, a second row 112, a third row 113, and a fourth row 114, and are arranged in three columns including a first column 121, a second column 122, and a third column 123. The first IC package tray 102 has an orientation facet surface 124 for indicating the location of the first row 111 and the first column 121 on the first IC package tray 102 as the row and the column nearest the orientation facet surface 124.
During use of the first IC package tray 102, each pocket of the first IC package tray 102 carries one respective IC package. The IC packages are placed into the pockets of the first IC package tray 102 in a predetermined sequential order. For the example of the first IC package tray 102 of FIG. 1, this predetermined sequential order is to first fill the first row 111 starting from the first column 121, then the second column 122, and then the third column 123 within the first row 111 of pockets. After the first row 111 of pockets is filled, the second row 112 of pockets is filled with IC packages starting from the first column 121, then the second column 122, and then the third column 123 within the second row 112 of pockets. After the second row 112 of pockets is filled, the third row 113 of pockets is filled with IC packages starting from the first column 121, then the second column 122, and then the third column 123 within the third row 113 of pockets. After the third row 113 of pockets is filled, the fourth row 114 of pockets is filled with IC packages starting from the first column 121, then the second column 122, and then the third column 123 within the fourth row 114 of pockets.
Depending on the size of IC packages being manufactured, different types of IC package trays have different numbers of pockets for carrying different numbers of IC packages. Referring to FIG. 2, for example, a second IC package tray 202 has twenty-four pockets for carrying twenty-four IC packages. The twenty-four pockets are arranged in four rows including a first row 211, a second row 212, a third row 213, and a fourth row 214, and are arranged in six columns including a first column 221, a second column 222, a third column 223, a fourth column 224, a fifth column 225, and a sixth column 226. The second IC package tray 202 has an orientation facet surface 230 for indicating the location of the first row 211 and the first column 221 on the second IC package tray 202 as the row and the column nearest the orientation facet surface 230. Referring to FIGS. 1 and 2, the first IC package tray 102 and the second IC package tray 202 have the same predetermined number of rows of pockets (i.e., four rows of pockets) but different numbers of columns of pockets (i.e., three columns of pockets for the first IC package tray 102 and six columns of pockets for the second IC package tray 202).
During use of the second IC package tray 202, each pocket of the second IC package tray 202 carries one respective IC package. The IC packages are placed into the pockets of the second IC package tray 202 in a predetermined sequential order. For the example of the second IC package tray 202 of FIG. 2, this predetermined sequential order is to first fill the first row 211 starting from the first column 221, then the second column 222, then the third column 223, then the fourth column 224, then the fifth column 225, and then the sixth column 226 within the first row 211 of pockets. After the first row 211 of pockets is filled, the second row 212 of pockets is filled with IC packages starting from the first column 221, then the second column 222, then the third column 223, then the fourth column 224, then the fifth column 225, and then the sixth column 226 within the second row 212 of pockets.
After the second row 212 of pockets is filled, the third row 213 of pockets is filled with IC packages starting from the first column 221, then the second column 222, then the third column 223, then the fourth column 224, then the fifth column 225, and then the sixth column 226 within the third row 213 of pockets. After the third row 213 of pockets is filled, the fourth row 214 of pockets is filled with IC packages starting from the first column 221, then the second column 222, then the third column 223, then the fourth column 224, then the fifth column 225, and then the sixth column 226 within the fourth row 214 of pockets.
In FIGS. 1 and 2, each IC package is placed within a pocket of the first IC package tray 102 or the second IC package tray 202 with proper orientation as indicated by an orientation marking (a circular marking) in the upper left corner of the IC package, as illustrated in FIGS. 1 and 2. During manufacture of IC packages, an IC package tray may be only partially filled. For example, in FIG. 1, the first IC package tray 102 is filled only to the pocket at the first column 121 of the third row 113. In FIG. 2, the second IC package tray 202 is filled only to the pocket at the second column 222 of the third row 213.
In any case, the number of IC packages within each of the IC package trays 102 and 202 is determined during manufacture of the IC packages. In the prior art, an operator manually counts the number of IC packages within a partially filled IC package tray for different types of IC package trays for carrying different numbers of IC packages. Unfortunately, the manual counting of the IC packages is prone to human error from fatigue as an operator continually counts the number of IC packages within numerous IC package trays during a work shift. The operator in some cases may count the number of IC packages in an IC package tray twice to ensure accuracy in counting the number of IC packages. Such a manual counting process of the prior art is also time-consuming.
Thus, a mechanism is desired for efficiently indicating the count of IC packages within a partially filled IC package tray for a plurality of types of IC package trays.
Accordingly, in a general aspect of the present invention, a mechanism includes a chest of counting grids for indicating a count of IC (integrated circuit) packages for a plurality of types of IC (integrated circuit) package trays. In one embodiment of the present invention, each of the plurality of types of IC package trays has a same predetermined number of rows of pockets for carrying IC packages, and each of the plurality of types of IC package trays has a respective number of columns of pockets for carrying IC packages.
In one aspect of the present invention, each counting grid of a plurality of counting grids has respective counting labels corresponding to a respective type of IC package tray. Each of the respective counting labels are arranged to be over a respective pocket of the respective type of IC package tray corresponding to a counting grid when the counting grid is placed over the respective type of IC package tray with the predetermined number of rows of counting labels on the counting grid being aligned to the predetermined number of rows of pockets of the respective type of IC package tray. In addition, the respective counting labels of the counting grid are numerically ordered according to an order of filling the pockets of the respective type of IC package tray.
In addition, a chest includes a bottom opening for holding an IC package tray that is partially filled with IC packages. The chest further includes a plurality of slots disposed through the chest with each slot holding a respective one of the counting grids disposed over and parallel with the IC package tray placed in the bottom opening of the chest such that the predetermined number of rows of counting labels of a counting grid are aligned to the predetermined number of rows of pockets of the IC package tray placed in the bottom opening of the chest. The chest also includes a plurality of viewing windows through the top of the chest with each viewing window being aligned over a respective one of the predetermined number of rows of pockets of the IC package tray placed in the bottom opening of the chest. Each row of counting labels of each of the counting grids within the chest is out of view through the viewing window when each of the counting grids are at a respective hidden position within the slots of the chest. However, a respective counting grid corresponding to the IC package tray placed in the bottom opening of the chest is placed to a respective visible position within the chest such that counting labels on the respective counting grid are visible through the plurality of viewing windows through the top of the chest. Then, a counting label of the respective counting grid over a last pocket to be filled within the IC package tray placed in the bottom opening of the chest indicates the count of IC packages within the IC package tray placed in the bottom opening of the chest.
In this manner, any of a plurality of types of IC package trays that is partially filled is placed at the bottom opening of the chest. The counting labels of a counting grid corresponding to the IC package tray placed at the bottom opening of chest is placed into view through the viewing windows of the chest. The counting label over a last pocket to be filled within the IC package tray placed in the bottom opening of the chest accurately indicates the count of IC packages within the IC package tray. Thus, an operator may be saved from the time and fatigue of manually counting the number of IC packages within numerous partially filled IC package trays for many different types of IC package trays during a work shift.
The present invention may also be practiced to particular advantage when each of the plurality of types of IC package trays has a same predetermined number of columns of pockets for carrying IC packages, and each of the plurality of types of IC package trays has a respective number of rows of pockets for carrying IC packages.
These and other features and advantages of the present invention will be better understood by considering the following detailed description of the invention which is presented with the attached drawings.